We do almost everything on our smartphones—from chatting with friends and ordering groceries to watching movies and monitoring sales and marketing campaigns for our small businesses. Living a day without our phones seems unusual. If it needs iPhone screen repair, we’ll have it fixed in a heartbeat. If it needs to be turned off for an event, most of us will simply put it on silent mode and checked it sneakily from time to time. That’s how we got so attached to using our smartphones in our daily lives.

While smartphones are beneficial for some aspects of our lives, they can still harm our physical and mental health. That is especially true when we don’t get enough sleep because we cannot put down our phones at night. Some can’t also focus on a task at hand as they stop to check their phone whenever they hear that distinct notification sound or see their phone lights up with an alert.

So, what’s with our phones that we get hooked on using them all day long? It’s the apps. Phone apps are designed to keep us engaged—they are intentionally addicting. And this design practice started in 2007.

It All Started with the “Facebook Class”

In September 2007, 75 students walked into BJ Fogg’s Persuasive Technology Lab at Stanford. About three months later, the students collectively amassed 16 million users using a formula taught by Fogg.

At that time, Facebook was in its third year. It started to open its platform to third-party developers. Fogg took this as an opportunity to test his signature framework on behavior design. Later called Fogg’s Behavior Model, the framework suggests that people act when motivation, trigger, and ability converge.

The model answers app designers’ most enduring question: How do you keep users coming back? Fogg’s 2007 class used this model to create their first batch of apps and many more after that year.

Eventually, this class, also known as “The Facebook Class,” graduated and went on to design products for Facebook and Uber. Some notable members of this class are Kevin Systrom and Mike Krieger, known as the founders of Instagram. The class also produced Tristan Harris, the former Google Design Ethicist, who becomes one of the most vocal whistleblowers of manipulative app design practices in Silicon Valley.

In many interviews, Harris shared three conscious design choices that cause phone addiction.

What Keeps You Glued to Your Smartphone

1. Push notifications

By employing push notifications, many smartphone apps emulate the feeling of social interaction—that another person wants to communicate with you—to motivate you to spend more time using them.

Blackberry first introduced push notifications in 2003, so users could check their phones less. You could easily see your emails as they came in—no need to browse your phone repeatedly to check your inbox.

But today, you can get notifications from any apps. These notifications don’t mean someone is trying to contact you; they vary from reminding you to get the daily game bonus to notifying you that a friend posted in their Facebook story. Harris explained that this variety is important as predictability would take out the addictiveness. It’s like a slot machine; you are motivated to pull the lever to see something new.

2. Bright colors

Human eyes are attracted to warm colors, especially red. That’s why fast-food store logos and many apps are in red. Remember the old brown camera logo of Instagram? The current logo still looks like a camera. But it now has a bright combo of red, purple, and yellow. The redesign aims to capture the attention of users. Again, like a slot machine full of bright, flashing lights, apps trigger your interest in using them.

3. Endless scrolling

Infinite scrolling makes the user experience seamless and convenient, but they also reduce your sense of control, making it harder for you to stop. After all, there is no endpoint. As humans, we rely on visual cues. We need an endpoint, like that Page 10 button on Google. So we know there’s no more to see.

The video auto-play feature on Netflix and YouTube works the same way. By disabling our ability to stop, smartphone apps intentionally let us get sucked in a bottomless vortex of digital indulgence. Think of that the next time you end up watching YouTube videos until three in the morning.

Now that you know how smartphone apps keep your attention and eat up your time, you can be more mindful of using your phone. Always ask yourself, what is genuinely worth your attention?

Meta title: Is Your Phone Addicting? A Stanford Class May Have a Hand in It

Meta desc: What’s with our smartphones that we get hooked on using them all day long? They are designed to be that way, and this design practice started in a class at Stanford.